1. Field of the Invention
The invention relates to a method of connecting a mobile, electronic control and/or monitoring unit to at least one machine or at least one machine component in a group or a plurality of machines or machine components to be monitored and/or controlled, for example industrial robots or manipulators, and an appropriate control and/or monitoring unit for this purpose, having an input device with several control elements and/or an optical display and having at least one interface co-operating with at least one control device for one or more machines or machine components, for example robots.
2. The Prior Art
An automation system with individual production cells consists of several machines or industrial robots programmed by an operator, and these have to equipped accordingly and optionally checked and monitored in order to set up a correct production sequence and obtain consistently high product quality. Mobile or portable electronic control units are used for this purpose, which more often than not enable the technical process to be displayed. The respective machines are usually arranged very close to one another and, because they are generally assigned to different processing tasks, these machines therefore have different control programmes for operating the requisite motion or processing sequence. A mobile control and/or monitoring unit must be designed for use with as many machines as possible in order to keep the number of control and/or monitoring units needed, and hence the costs of the technical plant, to a minimum. In order to be able to connect the control and/or monitoring unit to a specific machine, the operator generally has to enter identification numbers or codes from the hand terminal or select these from a list of codes. This is usually assisted by lists of references or plans relating to the installation and types of machines and this documentation has to be kept constantly up to date in order or prevent error sources.
The underlying objective of the present invention is to provide a connection method without increasing the complexity inherent in the requisite operation. Another objective of the invention is to provide a control and/or monitoring unit that is suitable for this purpose.
The objective is achieved by the invention due to the fact that in a connection or log-on procedure between the control and/or monitoring unit and the respective machine or a distant point on the machine, a clear connection or log-on link is set up by means of interfaces to the selected, wireless direction-finder of the corresponding distant point or by means of transmitters and/or receivers tuned to the transmission range or reception range, with a limited, localised functional or operating range and, once the connection has been acknowledged and established, the pre-programmed control and/or monitoring of the machine or the machine component is managed via another, standard data transmission means, for example a hard-wired network and/or via a wireless link between the control and/or monitoring unit and the selected machine or selected machine component. The advantage of this arrangement is that control and/or monitoring unit or the hand terminal used to control and/or observe an application can be operated in a manner that is totally logical and transparent to the operator. Furthermore, the connection as proposed by the invention is performed with the least possible risk of error and the connection sequence is clearly visible to the operator during the process. Another significant advantage of the features proposed by the invention resides in the fact that the log-on or connection procedure can be performed in a much shorter time so that the actual control or monitoring process can be performed sooner. Moreover, there is no longer any need to update or maintain documentation or plans, thereby ruling out another source of errors due to obsolete data, documentation or plans during control or monitoring. Consequently, the solution proposed by the invention enables a control and/or monitoring unit or a hand terminal to be logged on in a perfectly orderly and rapid manner to the applications which need to be controlled and/or monitored. In addition, there is barely any possibility of incorrect operation such as occurs when a number or an address has to be entered from a manual terminal. The method proposed by the invention therefore protects the machinery or the product to be manufactured and personnel from significant damage or injury. As a result of the directed or restricted geographical functional or operating range of the communication or transmission channel, the log-on or connection is very selective and incorrect connections can be virtually ruled out. The log-on or connection procedure is absolutely clear and logically transparent to the user. Another advantage is that the interfaces or the transmitters and/or receivers used to set up the transmission or communication channel may have a small bandwidth and are therefore relatively inexpensive to set up. The actual control and/or display data is in effect exchanged via the tried and tested, functionally safe data transmission means operated in an automation system of this type anyway.
A clear signal is indicated at least on the respective machine and/or on the control and/or monitoring unit when a link or connection has been established, which is an advantage because the user can be alerted to the fact that an operational connection has been established with the respective machine by acoustic and/or optical means.
Another advantage is that an active connection or log-on of a control and/or monitoring unit to one or more machines or machine components can not be terminated except by a deliberate or conscious log-off by the user, who must operate at least one control element of an input device of the control and/or monitoring unit or a control device of the machine or the machine component, which prevents the control and/or monitoring unit from being undesirably connected again or logged on again to another machine, thereby ruling out incorrect control procedures or erroneous monitoring procedures.
Because the link or log-on connection is cyclically checked against a valid log-on process and the control and/or monitoring unit is terminated either automatically or by the user, who simply quits by selecting the log-off option if the selected link or log-on connection goes down or is interrupted, a procedure to log off the control and/or monitoring unit can be operated extremely quickly and particularly easily.
During the procedure of logging on the control and/or monitoring unit, an identification number or code is transmitted and an acknowledgement returned, via the standard data transmission means or via the same wireless transmission channel, by the distant point or machine receiving this code, which also checks to ensure that the control and/or monitoring unit transmitting the code is valid, so that a specific machine or a specific machine component can not log on inadvertently or undesirably, nor can a specific machine or a specific machine component be controlled more than once.
The connection between the control and/or monitoring unit and the respective machine to be controlled and/or observed is effected automatically on entering the functional or operating range of the transmitter and/or receiver or simply by actively accepting/acknowledging the potential connection, which firstly makes for very easy operation and secondly means that a link or connection can only be made consciously by the user, thereby preventing undesirable connections.
Since the user can access the control and/or monitoring unit directly, a connection can be activated instantaneously and easily without the user having to switch locations.
The fact that the functional and operating range of the transmitters and/or receivers lies within the close immediate vicinity around the machines and/or around the control and/or monitoring unit means, firstly, that the hand terminal can not be connected to a machine unintentionally. Secondly, the hand terminal is prevented from connecting several times to machines located in the vicinity of one another.
Because the wireless connection is a radio link, mobility of the user terminal is virtually unlimited and cabling can be reduced to a minimum or dispensed with altogether.
The objective of the invention is also achieved by a control and/or monitoring unit having an input device with several operating elements and/or an optical display and having at least one interface to at least one control unit for one or more machines or machine components, for example robots. The advantage of this is that the connection or log-on procedure can be undertaken in a very short time and is also very conducive to preventing errors. In addition, the log-on procedure is simple to operate and users require very little in the way of training. The connection or log-on procedure proposed by the invention and operated via the hand terminal is very easy for the user to understand and offers the user a virtually intuitive procedure for selecting a machine or machine components.
The advantage of this arrangement is that the interface comprises a transmitter with a transmission characteristic that is directional or locally limited or restricted to the area in the immediate vicinity, which means that the control and/or monitoring unit can be unequivocally connected to the desired machine by a simple direction-finder of this machine or by simply positioning the control and/or monitoring unit in the immediate vicinity of the respective machine.
Another advantage is that the distant point comprises a receiver responding to the transmitter, which means that a one-way data transmission channel can be established and the number of components needed for the automated log-on or connection procedure can be kept to a minimum.
Another advantage is the fact that the distant point is provided as a receiver with a defined, limited reception sensitivity since this enables a clear and selective connection to be established and the transmitter can be rated to handle a relatively high transmission power or transmission range.
Another possibility is for the interface of the control and/or monitoring unit to have a receiver for signals transmitted in the region of a machine, by means of which the control and/or monitoring unit is allocated to the passive or receiving component and energy consumption of the control and/or monitoring unit and/or receiver can be kept low.
Due to the fact that the connection link-up between the transmitter and the receiver is uni-directional, an inexpensive system can beset up requiring few electronic or electro-mechanical components.
The interface is provided as an optical transmitter for infrared signals or laser light which means that a simple system can be set up for a directional transmission path between two units located at a distance apart from one another.
The interface is provided as a transmitter for electromagnetic waves, which enables a failsafe and transparent connection to be made across longer distances.
The transmitter and receiver co-operating with one another are provided as a transponder system, which offers an advantage in that the log-on procedure or the connection procedure can be carried out within an area of close proximity at a generally standard distance of between a few centimeters and about one meter. Of particular advantage is the fact that a transponder system of this type can be set up as a transmitter and/or receiver operating without batteries, so that the corresponding transponder can be connected to the hand terminal or the respective machine in a simple manner. This therefore obviates the need for complicated cabling or integration of the transponder in the electronic system of the control and/or monitoring unit or in the control device of the machine. A reading device for the transponder merely has to be provided, either on the machine to be controlled and/or monitored or on the hand terminal, which means only having to access a part region of the electronic control system. Furthermore, the transponder system can be used to set up a simple coding system for the connection procedure, in order to avoid or prevent multiple connections.
Advantage is to be had from a communication connection in which the interface is provided as an acoustic transmitter, for ultrasonic signals for example, since collisions or cross-connections with the existing infrared or radio links can be ruled out.
Another advantage is the fact that the interface is provided either in the form of contact pins and/or a contact rod or by means of an electrical contact surface with a complementary counter-contact on the machine to be controlled and/or monitored, because this means that the control and/or monitoring unit can be directly placed in contact with the corresponding distant point on the machine, at least for a brief period, thereby ruling out any incorrect connections.
Also of advantage is the fact that an operating element of the input device is provided for selectively logging on and terminating the connection, which means that a potential connection of the control and/or monitoring unit to a machine, automatically detected by the control system, is consciously initiated by the user, preventing undesirable communication links from being established. Alternatively or in combination with this feature, conditions or signals, which may, as an option, be automatically detected by the control system, to indicate that the communication link is to be effectively terminated or cut off, are actively cancelled by the user so that existing data or link connections can not be undesirably terminated.
Due to the fact that a distance-measuring device and/or a position sensor is provided as a means of detecting the distance of the control and/or monitoring unit relative to a machine or a machine component, a system can be set up by means of which connection and/or log-off conditions can be detected or monitored to a high degree of safety in terms of the pre-set direction or routing and/or as regards the predefined geographical vicinity of communication devices.
Finally, another advantage is gained by the fact that the interface is provided as a transmitter and/or receiver for signals to and/or from a distant point or transmitter and/or receiver co-operating therewith, disposed in the vicinity of the machines to be controlled and/or monitored since a two-way and/or a one-way communication route can be optionally set up. Particularly if using two-way communication, it is of advantage that a potential connection can be counter-checked, for example by exchanging and evaluating codes or addresses. This arrangement also allows status information to be exchanged, thereby offering highly reliable connection links using the so-called xe2x80x9chand-shakexe2x80x9d procedure. Furthermore, this will enable unintentional disconnections by parties to the link to be evaluated to enable defined or critical disconnections to be made.